Add TreeHash trait to all types and structs

eth2/types/src/attestation.rs

@@ -1,5 +1,5 @@
 use super::bls::AggregateSignature;
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::{AttestationData, Bitfield};
 use crate::test_utils::TestRandom;
 use rand::RngCore;
@@ -49,6 +49,17 @@ impl Attestation {
     }
 }
 
+impl TreeHash for Attestation {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.data.hash_tree_root());
+        result.append(&mut self.aggregation_bitfield.hash_tree_root());
+        result.append(&mut self.custody_bitfield.hash_tree_root());
+        result.append(&mut self.aggregate_signature.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for Attestation {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -76,4 +87,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = Attestation::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/attestation_data.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::Hash256;
 use crate::test_utils::TestRandom;
 use rand::RngCore;
@@ -85,6 +85,21 @@ impl Decodable for AttestationData {
     }
 }
 
+impl TreeHash for AttestationData {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.slot.hash_tree_root());
+        result.append(&mut self.shard.hash_tree_root());
+        result.append(&mut self.beacon_block_root.hash_tree_root());
+        result.append(&mut self.epoch_boundary_root.hash_tree_root());
+        result.append(&mut self.shard_block_root.hash_tree_root());
+        result.append(&mut self.latest_crosslink_root.hash_tree_root());
+        result.append(&mut self.justified_slot.hash_tree_root());
+        result.append(&mut self.justified_block_root.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for AttestationData {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -116,4 +131,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = AttestationData::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/attestation_data_and_custody_bit.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{Decodable, DecodeError, Encodable, hash, TreeHash, SszStream};
 use rand::RngCore;
 use crate::test_utils::TestRandom;
 use super::AttestationData;
@@ -30,6 +30,16 @@ impl Decodable for AttestationDataAndCustodyBit {
     }
 }
 
+impl TreeHash for AttestationDataAndCustodyBit {
+    fn hash_tree_root(&self) {
+        let result: Vec<u8> = vec![];
+        result.append(&mut self.data.hash_tree_root());
+        // TODO: add bool ssz
+        // result.append(custody_bit.hash_tree_root());
+        ssz::hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for AttestationDataAndCustodyBit {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -57,4 +67,16 @@ mod test {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = AttestationDataAndCustodyBit::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/beacon_block.rs

@@ -1,4 +1,4 @@
-use super::ssz::{ssz_encode, Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, ssz_encode, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::{BeaconBlockBody, Eth1Data, Hash256};
 use crate::test_utils::TestRandom;
 use bls::Signature;
@@ -61,6 +61,20 @@ impl Decodable for BeaconBlock {
     }
 }
 
+impl TreeHash for BeaconBlock {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.slot.hash_tree_root());
+        result.append(&mut self.parent_root.hash_tree_root());
+        result.append(&mut self.state_root.hash_tree_root());
+        result.append(&mut self.randao_reveal.hash_tree_root());
+        result.append(&mut self.eth1_data.hash_tree_root());
+        result.append(&mut self.signature.hash_tree_root());
+        result.append(&mut self.body.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for BeaconBlock {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -91,4 +105,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = BeaconBlock::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/beacon_block_body.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::{Attestation, CasperSlashing, Deposit, Exit, ProposerSlashing};
 use crate::test_utils::TestRandom;
 use rand::RngCore;
@@ -61,6 +61,21 @@ impl Decodable for BeaconBlockBody {
     }
 }
 
+impl TreeHash for BeaconBlockBody {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.proposer_slashings.hash_tree_root());
+        result.append(&mut self.casper_slashings.hash_tree_root());
+        result.append(&mut self.attestations.hash_tree_root());
+        result.append(&mut self.custody_reseeds.hash_tree_root());
+        result.append(&mut self.custody_challenges.hash_tree_root());
+        result.append(&mut self.custody_responses.hash_tree_root());
+        result.append(&mut self.deposits.hash_tree_root());
+        result.append(&mut self.exits.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for BeaconBlockBody {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -92,4 +107,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = BeaconBlockBody::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/beacon_state.rs

@@ -3,12 +3,12 @@ use super::eth1_data::Eth1Data;
 use super::eth1_data_vote::Eth1DataVote;
 use super::fork::Fork;
 use super::pending_attestation::PendingAttestation;
+use super::ssz::{hash, ssz_encode, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::validator::Validator;
 use super::Hash256;
 use crate::test_utils::TestRandom;
 use hashing::canonical_hash;
 use rand::RngCore;
-use ssz::{ssz_encode, Decodable, DecodeError, Encodable, SszStream};
 
 // Custody will not be added to the specs until Phase 1 (Sharding Phase) so dummy class used.
 type CustodyChallenge = usize;
@@ -166,6 +166,41 @@ impl Decodable for BeaconState {
     }
 }
 
+impl TreeHash for BeaconState {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.slot.hash_tree_root());
+        result.append(&mut self.genesis_time.hash_tree_root());
+        result.append(&mut self.fork_data.hash_tree_root());
+        result.append(&mut self.validator_registry.hash_tree_root());
+        result.append(&mut self.validator_balances.hash_tree_root());
+        result.append(&mut self.validator_registry_update_slot.hash_tree_root());
+        result.append(&mut self.validator_registry_exit_count.hash_tree_root());
+        result.append(&mut self.validator_registry_delta_chain_tip.hash_tree_root());
+        result.append(&mut self.latest_randao_mixes.hash_tree_root());
+        result.append(&mut self.latest_vdf_outputs.hash_tree_root());
+        result.append(&mut self.previous_epoch_start_shard.hash_tree_root());
+        result.append(&mut self.current_epoch_start_shard.hash_tree_root());
+        result.append(&mut self.previous_epoch_calculation_slot.hash_tree_root());
+        result.append(&mut self.current_epoch_calculation_slot.hash_tree_root());
+        result.append(&mut self.previous_epoch_randao_mix.hash_tree_root());
+        result.append(&mut self.current_epoch_randao_mix.hash_tree_root());
+        result.append(&mut self.custody_challenges.hash_tree_root());
+        result.append(&mut self.previous_justified_slot.hash_tree_root());
+        result.append(&mut self.justified_slot.hash_tree_root());
+        result.append(&mut self.justification_bitfield.hash_tree_root());
+        result.append(&mut self.finalized_slot.hash_tree_root());
+        result.append(&mut self.latest_crosslinks.hash_tree_root());
+        result.append(&mut self.latest_block_roots.hash_tree_root());
+        result.append(&mut self.latest_penalized_exit_balances.hash_tree_root());
+        result.append(&mut self.latest_attestations.hash_tree_root());
+        result.append(&mut self.batched_block_roots.hash_tree_root());
+        result.append(&mut self.latest_eth1_data.hash_tree_root());
+        result.append(&mut self.eth1_data_votes.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for BeaconState {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -217,4 +252,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = BeaconState::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/casper_slashing.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::SlashableVoteData;
 use crate::test_utils::TestRandom;
 use rand::RngCore;
@@ -31,6 +31,15 @@ impl Decodable for CasperSlashing {
     }
 }
 
+impl TreeHash for CasperSlashing {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.slashable_vote_data_1.hash_tree_root());
+        result.append(&mut self.slashable_vote_data_2.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for CasperSlashing {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -56,4 +65,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = CasperSlashing::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/crosslink.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::Hash256;
 use crate::test_utils::TestRandom;
 use rand::RngCore;
@@ -41,6 +41,15 @@ impl Decodable for Crosslink {
     }
 }
 
+impl TreeHash for Crosslink {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.slot.hash_tree_root());
+        result.append(&mut self.shard_block_root.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for Crosslink {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -66,4 +75,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = Crosslink::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/deposit.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::{DepositData, Hash256};
 use crate::test_utils::TestRandom;
 use rand::RngCore;
@@ -35,6 +35,16 @@ impl Decodable for Deposit {
     }
 }
 
+impl TreeHash for Deposit {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.merkle_branch.hash_tree_root());
+        result.append(&mut self.merkle_tree_index.hash_tree_root());
+        result.append(&mut self.deposit_data.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for Deposit {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -61,4 +71,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = Deposit::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/deposit_data.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::DepositInput;
 use crate::test_utils::TestRandom;
 use rand::RngCore;
@@ -35,6 +35,16 @@ impl Decodable for DepositData {
     }
 }
 
+impl TreeHash for DepositData {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.amount.hash_tree_root());
+        result.append(&mut self.timestamp.hash_tree_root());
+        result.append(&mut self.deposit_input.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for DepositData {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -61,4 +71,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = DepositData::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/deposit_input.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::Hash256;
 use crate::test_utils::TestRandom;
 use bls::{PublicKey, Signature};
@@ -36,6 +36,16 @@ impl Decodable for DepositInput {
     }
 }
 
+impl TreeHash for DepositInput {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.pubkey.hash_tree_root());
+        result.append(&mut self.withdrawal_credentials.hash_tree_root());
+        result.append(&mut self.proof_of_possession.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for DepositInput {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -62,4 +72,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = DepositInput::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/eth1_data.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::Hash256;
 use crate::test_utils::TestRandom;
 use rand::RngCore;
@@ -32,6 +32,15 @@ impl Decodable for Eth1Data {
     }
 }
 
+impl TreeHash for Eth1Data {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.deposit_root.hash_tree_root());
+        result.append(&mut self.block_hash.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for Eth1Data {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -57,4 +66,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = Eth1Data::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/eth1_data_vote.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::Eth1Data;
 use crate::test_utils::TestRandom;
 use rand::RngCore;
@@ -32,6 +32,15 @@ impl Decodable for Eth1DataVote {
     }
 }
 
+impl TreeHash for Eth1DataVote {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.eth1_data.hash_tree_root());
+        result.append(&mut self.vote_count.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for Eth1DataVote {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -57,4 +66,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = Eth1DataVote::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/exit.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use crate::test_utils::TestRandom;
 use bls::Signature;
 use rand::RngCore;
@@ -35,6 +35,16 @@ impl Decodable for Exit {
     }
 }
 
+impl TreeHash for Exit {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.slot.hash_tree_root());
+        result.append(&mut self.validator_index.hash_tree_root());
+        result.append(&mut self.signature.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for Exit {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -61,4 +71,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = Exit::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/fork.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use crate::test_utils::TestRandom;
 use rand::RngCore;
 
@@ -34,6 +34,16 @@ impl Decodable for Fork {
     }
 }
 
+impl TreeHash for Fork {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.pre_fork_version.hash_tree_root());
+        result.append(&mut self.post_fork_version.hash_tree_root());
+        result.append(&mut self.fork_slot.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for Fork {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -60,4 +70,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = Fork::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/pending_attestation.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::{AttestationData, Bitfield};
 use crate::test_utils::TestRandom;
 use rand::RngCore;
@@ -39,6 +39,17 @@ impl Decodable for PendingAttestation {
     }
 }
 
+impl TreeHash for PendingAttestation {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.data.hash_tree_root());
+        result.append(&mut self.aggregation_bitfield.hash_tree_root());
+        result.append(&mut self.custody_bitfield.hash_tree_root());
+        result.append(&mut self.custody_bitfield.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for PendingAttestation {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -66,4 +77,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = PendingAttestation::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/proposal_signed_data.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::Hash256;
 use crate::test_utils::TestRandom;
 use rand::RngCore;
@@ -35,6 +35,16 @@ impl Decodable for ProposalSignedData {
     }
 }
 
+impl TreeHash for ProposalSignedData {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.slot.hash_tree_root());
+        result.append(&mut self.shard.hash_tree_root());
+        result.append(&mut self.block_root.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for ProposalSignedData {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -61,4 +71,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = ProposalSignedData::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/proposer_slashing.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::ProposalSignedData;
 use crate::test_utils::TestRandom;
 use bls::Signature;
@@ -44,6 +44,18 @@ impl Decodable for ProposerSlashing {
     }
 }
 
+impl TreeHash for ProposerSlashing {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.proposer_index.hash_tree_root());
+        result.append(&mut self.proposal_data_1.hash_tree_root());
+        result.append(&mut self.proposal_signature_1.hash_tree_root());
+        result.append(&mut self.proposal_data_2.hash_tree_root());
+        result.append(&mut self.proposal_signature_2.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for ProposerSlashing {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -72,4 +84,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = ProposerSlashing::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/shard_committee.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use crate::test_utils::TestRandom;
 use rand::RngCore;
 
@@ -24,6 +24,15 @@ impl Decodable for ShardCommittee {
     }
 }
 
+impl TreeHash for ShardCommittee {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.shard.hash_tree_root());
+        result.append(&mut self.committee.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for ShardCommittee {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -49,4 +58,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = ShardCommittee::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/shard_reassignment_record.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use crate::test_utils::TestRandom;
 use rand::RngCore;
 
@@ -34,6 +34,16 @@ impl Decodable for ShardReassignmentRecord {
     }
 }
 
+impl TreeHash for ShardReassignmentRecord {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.validator_index.hash_tree_root());
+        result.append(&mut self.shard.hash_tree_root());
+        result.append(&mut self.slot.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for ShardReassignmentRecord {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -60,4 +70,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = ShardReassignmentRecord::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/slashable_vote_data.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use super::ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 use super::AttestationData;
 use crate::test_utils::TestRandom;
 use bls::AggregateSignature;
@@ -40,6 +40,17 @@ impl Decodable for SlashableVoteData {
     }
 }
 
+impl TreeHash for SlashableVoteData {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.custody_bit_0_indices.hash_tree_root());
+        result.append(&mut self.custody_bit_1_indices.hash_tree_root());
+        result.append(&mut self.data.hash_tree_root());
+        result.append(&mut self.aggregate_signature.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for SlashableVoteData {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -67,4 +78,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = SlashableVoteData::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/special_record.rs

@@ -1,4 +1,4 @@
-use super::ssz::{Decodable, DecodeError, Encodable, SszStream};
+use ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 
 /// The value of the "type" field of SpecialRecord.
 ///
@@ -71,6 +71,15 @@ impl Decodable for SpecialRecord {
     }
 }
 
+impl TreeHash for SpecialRecord {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.kind.hash_tree_root());
+        result.append(&mut self.data.as_slice().hash_tree_root());
+        hash(&result)
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

eth2/types/src/validator.rs

@@ -2,7 +2,7 @@ use super::bls::PublicKey;
 use super::Hash256;
 use crate::test_utils::TestRandom;
 use rand::RngCore;
-use ssz::{Decodable, DecodeError, Encodable, SszStream};
+use ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 
 const STATUS_FLAG_INITIATED_EXIT: u8 = 1;
 const STATUS_FLAG_WITHDRAWABLE: u8 = 2;
@@ -142,6 +142,24 @@ impl Decodable for Validator {
     }
 }
 
+impl TreeHash for Validator {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.pubkey.hash_tree_root());
+        result.append(&mut self.withdrawal_credentials.hash_tree_root());
+        result.append(&mut self.proposer_slots.hash_tree_root());
+        result.append(&mut self.activation_slot.hash_tree_root());
+        result.append(&mut self.exit_slot.hash_tree_root());
+        result.append(&mut self.withdrawal_slot.hash_tree_root());
+        result.append(&mut self.penalized_slot.hash_tree_root());
+        result.append(&mut self.exit_count.hash_tree_root());
+        result.append(&mut (status_flag_to_byte(self.status_flags) as u64).hash_tree_root());
+        result.append(&mut self.latest_custody_reseed_slot.hash_tree_root());
+        result.append(&mut self.penultimate_custody_reseed_slot.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for Validator {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -198,4 +216,16 @@ mod tests {
             }
         }
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = Validator::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }

eth2/types/src/validator_registry_delta_block.rs

@@ -2,7 +2,7 @@ use super::Hash256;
 use crate::test_utils::TestRandom;
 use bls::PublicKey;
 use rand::RngCore;
-use ssz::{Decodable, DecodeError, Encodable, SszStream};
+use ssz::{hash, Decodable, DecodeError, Encodable, SszStream, TreeHash};
 
 // The information gathered from the PoW chain validator registration function.
 #[derive(Debug, Clone, PartialEq)]
@@ -58,6 +58,18 @@ impl Decodable for ValidatorRegistryDeltaBlock {
     }
 }
 
+impl TreeHash for ValidatorRegistryDeltaBlock {
+    fn hash_tree_root(&self) -> Vec<u8> {
+        let mut result: Vec<u8> = vec![];
+        result.append(&mut self.latest_registry_delta_root.hash_tree_root());
+        result.append(&mut self.validator_index.hash_tree_root());
+        result.append(&mut self.pubkey.hash_tree_root());
+        result.append(&mut self.slot.hash_tree_root());
+        result.append(&mut self.flag.hash_tree_root());
+        hash(&result)
+    }
+}
+
 impl<T: RngCore> TestRandom<T> for ValidatorRegistryDeltaBlock {
     fn random_for_test(rng: &mut T) -> Self {
         Self {
@@ -86,4 +98,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_hash_tree_root() {
+        let mut rng = XorShiftRng::from_seed([42; 16]);
+        let original = ValidatorRegistryDeltaBlock::random_for_test(&mut rng);
+
+        let result = original.hash_tree_root();
+
+        assert_eq!(result.len(), 32);
+        // TODO: Add further tests
+        // https://github.com/sigp/lighthouse/issues/170
+    }
 }